Table 1.

Simulation results.

n	Purposeful	Stepwise	Backward	Forward
60	5.1	4.5	4.9	9
120	24.2	22.4	22.8	24.2
240	52.6	52.6	52.5	36
360	69.8	69.8	69.8	42.5
480	71.1	71.2	71.1	44.2
600	70.5	70.6	70.5	40.4

Retention of the correct model for purposeful, stepwise, backward, and forward selection methods, with no confounding present.